With proper selective breeding a Halfmoon should be balanced even with the big finnage and not look like a big finned guppy dragging their tail around. That male as nice as he is would have points taken off in a show for too small of a caudal. Like I said though I would love to have him. One of my favorite males had some humongous finnage but in order to continue the line without over developing the finnage I had to breed him with a female from a smaller finned line.